Multiple position switch



March 1956 E. s. LESLIE ET AL 2,740,005

MULTIPLE POSITION SWITCH Filed June 26, 1953 2 Sheets-Sheet l l INVENTORS EDWARD s. LESLIE 8 JAMES 1.. PETTUS 30 y ZM/M ATTORNEY March 1956 E. s. LESLIE ET AL 2,740,005

MULTIPLE POSITION SWITCH Filed June 26, 1953 2 Sheets-Sheet 2 FI EL 159E.

iNVENTORS EDWARD S. LESLIE 6 JAMES L. PETTUS ATTORNEY United States Patent 2,740,005 MULTIPLE POSITION SWITCH Edward S. Leslie, Van Nuys, and James L. Pettus, Encino, assignors to Radio Corporation of America, a corporation of Delaware Application June 26, 1953, Serial No. 364,394 4 Claims. (Cl. 200-47) This invention relates to electrical switching systems, and particularly to a switch mechanism for connecting a plurality of electrical elements, such as the motors of distributors, reproducers, and recorders without making connections with other circuits during the switching operation.

In many types of electrical systems, and particularly in motion picture production, several motors are operated in synchronism as an interlock system. A distributor connected to the motors of the respective units controls the speed of film advancement in sound reproducers, recorders, cameras, and similar units. A system of this general type is disclosed and claimed in Bloomberg et al. U. S. Patent No. 2,445,820 of July 27, 1948. The present invention simplifies the switch mechanism disclosed in this patent. Also, in a co-pending U. S. application, Ser. No. 364,340, filed June 26, 1953, an H type switch mechanism for this purpose is disclosed and claimed. To simplify the switch of the present invention, it utilizes a transverse slot with a control knob in the form of a wrench, which may be moved to a plurality of positions for connecting any particular motor unit to any selected one of several other units without making contact with the circuit of any other unit which may be connected.

The principal object of the invention, therefore, is to facilitate the switching and interconnection of several electrical units, such as motors.

Another object of the invention is to provide an improved multiple position switching mechanism which may connect any one of a plurality of contacts without making any other contact except the one desired.

A further object of the invention is to provide an improved multiple position switch which is simple, rugged, and economical.

Although the novel features which are believed to be characteristic of this invention will be pointed out with particularity in the appended claims, the manner of its on ganization and the mode of its operation will be better understood by referring to the following description, read in conjunction with the accompanying drawings, forming a part hereof, in which:

Fig. 1 is an elevational view of a switching mechanism embodying the invention.

Fig. 2 is a cross-sectional view taken along the line 2-2 of Fig. 1.

Fig. 3 is a cross-sectional view taken along the line 33 of Fig. 1.

Fig. 4 is a detailed cross-sectional view taken along the line 4-4 of Fig. 3.

Fig. 5 is a diagrammatic view showing one adjusted position of the switch mechanism and taken along the line 5-5 of Fig. 2.

Fig. 6 is a diagrammatic view showing another adjusted position of the switching mechanism, and

Fig. 7 is a single line drawing of a system in which the invention is used.

Referring now to the drawings, and particularly to Fig. 7, a system is shown employing four distributors, Nos. 1,

2, 3, and 4. Also shown in Fig. 7 is a photographic reproducer 6, a photographic recorder 7, and a magnetic recorder 8. The photographic reproducer is connected to the movable swingers 14 and 20 of a switch 10, photographic recorder 7 is connected to the movable swingers 22 and 24 of a switch 11, and the magnetic recorder 8 is connected to the movable swingers 26 and 27 of a switch 12. To connect the photographic reproducer 6 to distributor 1, the upper swinger 14 of switch is connected to conductor 15 leading to distributor 1 over conductor 16. Similarly, distributor 2 may be connected to photographic reproducer 6 by moving the swinger 14 to its lower position, the circuit being over conductors 18 and 19. Swinger 20 of switch 10 will connect the photographic reproducer to distributors 3 and 4 if in its upper or lower positions, respectively, over obvious conductors.

Similarly, switch 11 with its swingers 22 and 24 will connect the photographic recorder 7 to any one of the distributors 1, 2, 3, or 4 and switch 12 with its swingers 26 and 27 will connect magnetic recorder 8 to any one of the distributors over obvious conductors. Other units may also be similarly connected to the extension of the conductors from the distributors.

Referring now to the other figures, a mounting plate 30 has mounted over an opening 34 therein a switch plate 31 attached thereto by screws 32. The opening 34 is in the form of an elongated rectangular slot with circular end openings, as shown at 35. Mounted also on the mounting plate 30 are a pair of switches 37 and 38 having actuating elements 39 and 40 in the form of shafts or rods having square ends. The switches are connected to the plate by brackets 42 and 43.

Mounted in the slot 34 is a switch knob 45 having a flat sided shaft 46 with a slotted end 47. The knob unit is held in the slot by a pair of washers 48 and 49. The knob 45 is mounted on a rod 51 of the shaft 46 by set screw 52.

Considering one of the Fig. 7-the swinger swinger 20 by shaft switches-namely, switch 10 of 14 is operated by shaft 39 and the 40. Thus, to move the swinger 14 knob wrench is moved to the shaft 39. It is then rotated to number 3 position in the enlarged circular end, as shown in Fig. I. For swinger 20 to make its lower contact, the knob is rotated to position 4, as shown in Fig. 6. If it is desired to have swinger 20 make its upper contact, the knob is rotated back to its neutral position and then moved to the left and rotated to the number 1 position, as shown in Fig. 1. To have swinger 20 make its lower contact, the knob 45 is rotated to the number 2 position.

Since the shaft 46 has fiat sides, it cannot be moved into the slot 34 from either end position where it is rotatable until it is returned to its neutral or off position, as shown in Fig. 1. In this manner, no connection can be made between any of the units 6, 7, and 8 with any of the distributors 1, 2, 3, and 4 without first breaking any former connection between the particular unit and the particular distributor. Furthermore, no connection is made with any other motor or distributor circuit in the operation of switching from one unit to another. This is a safety feature which has been provided in a simple and rugged mechanism, which is easily maintained. A plurality of these switches may be arranged on a rack or panel for accessibility and ease of operation.

Also, the slot 34 may be extended beyond the ends 35 to operate other switches with the same knob wrench in the same manner. The slot 34 may also be circular with several enlarged positions to permit the rotation of the knob wrench. In these ways, many switches may be acmated with the same knob wrench.

We claim:

1. A switching mechanism comprising a plate having an elongated slot therein with enlarged circular ends, a pair of switches, actuating shafts for said switches, said shafts having square ends, and a rotatable switch knob wrench including a shaft with a slotted end adapted to accommodate the square ends of said switch actuating shafts, said knob shaft having flat parallel sides, one dimension between two opposite sides being substantially the width of said slot, and the dimension between sides perpendicular to said first-mentioned sides being greater than the width of said slot, said shaft being movable from one end of said panel slot only when said sides having the smaller dimension between them are parallel with the sides of said slot.

2. A switch mechanism comprising a panel having an elongated slot therein with enlarged circular portions, a switch knob having a flat sided shaft with a flat sided notch in the end thereof, one dimension between two op posite sides of said shaft being substantially the width of said slot, and the dimension between sides perpendicular to said first-mentioned sides being greater than the width of said slot, said shaft being rotatable when in the circular portions of said slot and movable from one circular portion of said slot to another circular portion when in a certain predetermined position of rotation, said position of rotation occurring when the said sides having the smaller dimension between them are parallel with the sides of said slot, and switch actuating means having square ends adjacent said-circular portions and adapted to be rotated by said knob when the ends thereof are in said notch in said knob shaft.

3. A four-position switch mechanism in accordance with claim 2, in which switch contacts are provided, said contacts being made by the rotation of said actuating means with square ends.

4. A switching mechanism comprising a pair of switches, each having two contact positions, a rod for each switch having a square end for actuating each of said switches, a panel having an elongated slot therein with circular enlarged openings, the axis of each rod coinciding with the center of each of said openings, and Wrench means movable in said slot for rotating said rods, said wrench means including a knob having a flat sided shaft in said elongated slot, one dimension between two opposite sides of said shaft being substantially the width of said slot, and the dimension between sides perpendicular to said first-mentioned sides being greater than the Width of said slot, said shaft being rotatable only in said openings and having a fiat sided notch in the end thereof to accommodate the square ends of said rods.

References Cited in the file of this patent UNITED STATES PATENTS 

